tomspark wrote:
popuman's got it right. For an OptiPlex I'd go with Ubuntu Server (the latest LTS version) — it's the most-tested path for SparkBox and our install docs are written against it, so you'll hit the fewest surprises. Skip the desktop version; you don't need a screen on it once it's running. Once Ubuntu's on there, the SparkBox install is one command straight from the docs. Easy little box to run this on — you'll be fine.